BECKHOFF C33xx - Manual (Page 21)

Operating Instructions
The Esc key has the effect of closing dialog windows and of interrupting
some of the computer’s working operations.
Q W
...
1
!
2
@
All other keys bring the character printed on them onto the display at the
position of the cursor.
Function keys
F1 F2 F3 F4
F5 F6 F7 F8
F9 F10 F11 F12
The meaning of the function keys, F1 to F10, is determined by the software
and is displayed at the bottom edge of the display.
Special keys
The function of the special keys left beside the display is also determined
by the software. The function is displayed at the top edge of the display or
by the marked module strips.
The special keys each have an orange LED controlled by the software.
C33xx 19